Dynamic Q Angle and Core Endurance in Adolescent Athletes With Patellofemoral Pain Syndrome

NCT07328750 | Completed

• 1 other identifier: PFAS-QCORE-2025
• Study Type: observational
• Target: 150
• Locations: 1 country
• Sites: 1

Brief Summary

This observational, cross-sectional study aimed to compare dynamic Q-angle, trunk/core endurance, and lower-extremity flexibility between elite adolescent female and male sprinters with and without patellofemoral pain syndrome (PFPS). Participants were classified according to sex and PFPS status. Dynamic Q-angle was assessed during a standardized step-down task, trunk endurance was evaluated using McGill flexion, extension, and lateral endurance tests, and lower-extremity flexibility was assessed using the Straight Leg Raise, Modified Thomas, and Ober tests. The study also examined whether sex and PFPS status were independently associated with dynamic Q-angle. No therapeutic or experimental intervention was administered.

Conditions

Patellofemoral Pain Syndrome; Anterior Knee Pain Syndrome

Keywords

Dynamic Q Angle; Core Endurance; Lower Extremity Function; Sports-Specific Biomechanics; Elite Athletes; Adolescent Sports Performance

Outcome Measures

Primary Outcomes (1)

• Dynamic Q-Angle During the Step-Down Test (degrees)

  Dynamic Q-angle was assessed during a standardized step-down task from a 16-cm platform using the DrGoniometer mobile application. Anatomical markers were placed over the anterior superior iliac spine, center of the patella, and tibial tuberosity. Two repetitions were recorded in the frontal plane, and the mean angle was used for analysis. In participants with PFPS, the symptomatic extremity was assessed; in participants without PFPS, the corresponding matched extremity was used.

  Baseline (single assessment at study enrollment)

Secondary Outcomes (4)

• Trunk/Core Endurance Test Duration (seconds)

  Baseline (single assessment at study enrollment)

• Hamstring Flexibility - Straight Leg Raise Angle (degrees)

  Baseline (single assessment at study enrollment)

• Hip Flexor Flexibility - Modified Thomas Test Angle (degrees)

  Baseline (single assessment at study enrollment)

• Iliotibial Band and Tensor Fasciae Latae Flexibility - Ober Test Angle (degrees)

  Baseline (single assessment at study enrollment)

Study Arms (4)

Female Sprinters Without PFPS

Elite adolescent female sprinters aged 15-17 years without current anterior knee pain or clinical findings consistent with patellofemoral pain syndrome. Participants underwent a single standardized assessment of dynamic Q-angle, trunk/core endurance, and lower-extremity flexibility. No therapeutic or experimental intervention was administered.

Female Sprinters With PFPS

Elite adolescent female sprinters aged 15-17 years diagnosed with patellofemoral pain syndrome by a sports medicine physician. Participants underwent a single standardized assessment of dynamic Q-angle, trunk/core endurance, and lower-extremity flexibility. No therapeutic or experimental intervention was administered.

Other: Patellofemoral Pain Syndrome Status

Male Sprinters Without PFPS

Elite adolescent male sprinters aged 15-17 years without current anterior knee pain or clinical findings consistent with patellofemoral pain syndrome. Participants underwent a single standardized assessment of dynamic Q-angle, trunk/core endurance, and lower-extremity flexibility. No therapeutic or experimental intervention was administered.

Male Sprinters With PFPS

Elite adolescent male sprinters aged 15-17 years diagnosed with patellofemoral pain syndrome by a sports medicine physician. Participants underwent a single standardized assessment of dynamic Q-angle, trunk/core endurance, and lower-extremity flexibility. No therapeutic or experimental intervention was administered.

Other: Patellofemoral Pain Syndrome Status

Interventions

Patellofemoral Pain Syndrome Status OTHER

Participants were classified as having patellofemoral pain syndrome (PFPS) or not having PFPS based on a clinical assessment performed by a sports medicine physician. PFPS classification was based on anterior knee pain symptoms, positive patellofemoral clinical tests, an Anterior Knee Pain Scale score below 80, and a Visual Analog Scale pain score of at least 3. Biological sex was used as an additional grouping factor. No therapeutic, exercise, pharmacological, or experimental intervention was administered.

Also known as: PFPS Status, Anterior Knee Pain Status

Female Sprinters With PFPS; Male Sprinters With PFPS

Eligibility Criteria

• Age: 15 Years - 17 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)
• Sampling Method: Non-Probability Sample

Study Population

Elite female and male adolescent sprinters aged 15-17 years who were actively competing in national or international sprint events. Participants were evaluated at the Physiotherapy and Rehabilitation Clinic of the Adana Olympic Preparation Center, Provincial Directorate of Youth and Sports, Adana, Türkiye. Participants were classified according to biological sex and the presence or absence of patellofemoral pain syndrome.

You may qualify if:

• Female or male adolescent elite sprinters aged 15-17 years Minimum of two years of regular athletic training Participation in athletic training at least four days per week Possession of a valid track and field license Active participation in sprint events at the national or international level Ability to complete all clinical and biomechanical assessments Written informed consent from the participant and a parent or legal guardian
• PFPS Group-Specific Criteria:
• Diagnosis of patellofemoral pain syndrome by a sports medicine physician Anterior knee pain localized to the patellofemoral region Positive patellar compression and grind test Anterior Knee Pain Scale score below 80 Visual Analog Scale pain score of at least 3
• Control Group-Specific Criteria:
• No current anterior knee pain No clinical findings consistent with patellofemoral pain syndrome

You may not qualify if:

• History of lower-extremity surgery Acute lower-extremity injury within the previous six months Notable musculoskeletal deformity Arthritis or chronic pain affecting the knee, hip, or ankle Neurological or systemic disease that could affect movement or physical performance Inability to complete the assessments because of excessive pain or insufficient cooperation Incomplete assessment data

Sponsors & Collaborators

• Eastern Mediterranean University: lead

Study Sites (1)

Burcin Ugur Tosun

Adana, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Patellofemoral Pain Syndrome

Condition Hierarchy (Ancestors)

Joint Diseases; Musculoskeletal Diseases

Study Officials

• burcin ugur tosun

  Ministry of Youth and Sports, Olympic Preparation Center, Adana, Türkiye

  STUDY CHAIR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator PhD Physiotherapist Burcin Ugur Tosun

Study Record Dates

• First Submitted: December 26, 2025
• First Posted: January 9, 2026
• Study Start: December 1, 2025
• Primary Completion: February 15, 2026
• Study Completion: February 20, 2026
• Last Updated: July 20, 2026

Record last verified: 2026-07

Locations

TU (1)